SOLVED Malachite (Revv G2) SOLVED

I just built one, and I'm not getting audio output. Any update on when the schematic will be released? Thanks.
 
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I notice a discrepancy between my physical board and the rendering on the site. There may be more, but I stopped when I noticed it as I was troubleshooting using a continuity tester to trace my board compared to the rendering on the site, since a schematic doesn't exist yet. I don't know that this is related to my problem.

In the rendering, pin 3 of the treble pot has a trace that goes to the 2nd cap down, LH column, as shown below. In the actual board, the trace goes to the 3rd cap down, shown in the second pic. Any thoughts?

Malachite Rendering.jpg Malachite Pic.jpg
 
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most of the time there are several versions of the same circuit, which improve with each new PCB, if I had to check this out, I'll use the REVV G4 schematic as a reference plus solder joints, all the outputs of each IC etc. the regular stuff, also reading other build problems and solutions helps a lot :)
 
I don't think that's the case here, as it's new.

The only one who knows for sure is Mr. PEDALPCB

Agreed. But I don't think that's the case here, as it's new. If you search, you won't find other Malachite build threads.

I mean different pedal builds have most of the time the same issues
 
PCBs sometimes see two or three (or more) revisions before they're ever released. Don't rely on the preview images, especially when there are no component values listed.... That's a good sign that modifications were expected to happen.

I've mentioned this before, component values aren't omitted from the previews in an attempt to hide anything... They're omitted in the early stages to prevent people from ordering parts that might be changed before the release.

 
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I just built one, and I'm not getting audio output. Any update on when the schematic will be released? Thanks.
Check to see you have correct Continuity on your Toggle Switch, They look (Pads) like they got a lot of Heat.
I assume you are getting Sound in Bypass.
Did you use the Jacks with Multiple terminals.
Post pictures of Front & Back including Footswitch & Jacks if you still have Issue.
 
Check to see you have correct Continuity on your Toggle Switch.

Thank you for your comments. It checked fine.

I assume you are getting Sound in Bypass.

Yes.

Did you use the Jacks with Multiple terminals.

No, the kind with (1) terminal for the tip and (1) for the sleeve.

Post pictures of Front & Back including Footswitch & Jacks if you still have Issue.

Attached. I removed the 2PDT switch to make it easier to get my meter to the board. Same reason I swung the (2) inner pots upward...
20191113_082356-2.jpg
20191113_082419-2.jpg
 
Can you tell me why the PCB Power Led Anode & Cathode has a Jumper. I presume your using PCB 4K7 resistor & SW goes to +V on Footswitch PCB.
Have you plugged it in as it is shown above without the Toggle switch to see if it fires up.
 
Can you tell me why the PCB Power Led Anode & Cathode has a Jumper.

See the first photo, and see the LEDs (there are 6) that surround the footswitch? I'm using that instead. It's either those or the onboard one, and I like the surround LED switch thing. I've done a dozen pedals this way, it works great. Notice there is also a jumper on the sub-board that is attached the 3PDT switch. That would normally have a resistor there as well, except I use the onboard (PedalPCB) resistor, so I jumper that too.

Have you plugged it in as it is shown above without the Toggle switch to see if it fires up.

Yes, same behavior. Which is why need the schematic, to get in with my audio probe to find where the signal ends. I can tell you, with my audio probe, the signal sounds "right" (well, distorted anyway) at certain points within the circuit, so clearly some of circuit is "right", but it's not getting to the output.
 
See the first photo, and see the LEDs (there are 6) that surround the footswitch? I'm using that instead. It's either those or the onboard one, and I like the surround LED switch thing. I've done a dozen pedals this way, it works great. Notice there is also a jumper on the sub-board that is attached the 3PDT switch. That would normally have a resistor there as well, except I use the onboard (PedalPCB) resistor, so I jumper that too.



Yes, same behavior. Which is why need the schematic, to get in with my audio probe to find where the signal ends. I can tell you, with my audio probe, the signal sounds "right" (well, distorted anyway) at certain points within the circuit, so clearly some of circuit is "right", but it's not getting to the output.
I reworded the Question as you were Responding, All Good.
 
You should be getting around 4.2v to Pins 1 2 3 5 6 7 on all 3 Op Amps & around 8.4v on Pins 8.

First of all, thank you. I just checked, and I have found (2) pins on the first (top, highest) TL072 out of range. Pins 5 & 7 (top, highest) came back at ~1.3V

Every other pin on all (3) TL072's were within ~5% of your values. I swapped the TL072 and the new one gave the same readings, so I believe you have helped me to start tracing from there. Greatly appreciated.

Question: how did you know what voltages were expected?
 
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